Two types of transmission station are known: "conventional" or outdoor stations; and "metal-clad" stations.
Conventional stations include apparatuses which are all interconnected by connections in air.
They have the advantage of making it possible to see when a section switch is open, and of occupying large working volumes with large safety distances which facilitate manual intervention by personnel.
They suffer from the drawback of occupying a large area on the ground and this is a serious drawback in the vicinity of towns where land prices are continually rising.
In metal-clad stations, connections are provided by busbars placed inside gas-tight tubes which are insulated by sulfur hexafluoride, and they occupy much less space.
However, they suffer from several drawbacks: the distances between apparatuses do not make manual intervention easy.
It is not possible to see whether a metal-clad section switch is in the open state or the closed state, and this is not favorable to personnel safety.
An object of the present invention is to provide a high tension electricity station occupying a smaller ground area than conventional type stations while retaining their qualities with respect to operation (visibly open circuits, considerable working and safety distances).